[GHC] #7952: Can cost-centre annotations be included in -ddump-simpl?

[GHC]

#7952: Can cost-centre annotations be included in -ddump-simpl?
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    Reporter:  nr                |       Owner:                  
        Type:  feature request   |      Status:  new             
    Priority:  normal            |   Milestone:                  
   Component:  Compiler          |     Version:  7.6.3           
    Keywords:  Core              |          Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |     Failure:  None/Unknown    
  Difficulty:  Unknown           |    Testcase:                  
   Blockedby:                    |    Blocking:                  
     Related:                    |  
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Changes (by simonpj):

 * cc: simonmar (added)
  * difficulty:  => Unknown


Comment:

 I'm not terribly up to speed with the state of cost-centre profiling.

 In general, the cost centre (or cost-centre stack) to which a `let`
 allocation is attributed is a ''dyanamic'' property; it depends on the
 caller of the current function. (Eg to which cost centre are the thunks
 allocated by `map` attributed?  Answer: the caller.)   So it's not clear
 that your question has a meaningful answer.

 Simon Marlow will know the current state of affairs, and embarrassingly I
 can't even point to a document that I am sure reflects the current state
 of affairs.  Maybe Simon can.

 The whole area is in need of love and attention from someone who (a) has
 excellent operational intuitions, and (b) takes a strongly principled
 approach.  Norman Ramsey comes to mind.

 Simon

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7952#comment:1>
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